Xiaomi has unveiled a brand new concept phone, and this one features something of a first: a four-sided waterfall display. 

That means the glass around all four sides of the screen curves down until it's almost perpendicular to the main surface of the screen. Specifically: it features an 88-degree curve. 

Given that so many phones are moving back towards flat displays for practicality (and the fact skinny bezels are possible now), it's a bold and interesting move from the manufacturer. 

As with most concepts - like the Vivo Apex - this is more about showing what's possible, not necessarily about developing features that enhance the user experience. Check it out in the video below: 

Xiaomi says it was able to do this by developing a new 3D bonding process for the glass. The company had to use a hot bending process, heating the glass to 800 degrees Celsius, adding pressure and then also going through a ten stage polishing process. 

While it is incredibly interesting, it's worth noting one thing: it doesn't seem Xiaomi has yet been able to solve the problem of having the screen also curving around the corners of the phone. 

You'll notice if you look carefully at the corners that they feature a sort-of curved cutout where the screen wraps around the sides. 

In addition to featuring a four-sided curved screen, the Xiaomi concept is also a portless phone. That means no physical buttons, no USB-C port, no headphone jack and no visible speaker grille or SIM tray. 

This means using the surface of the phone's glass as a 'speaker' of sorts - using similar piezoelectric tech we've seen in other portless phones before - plus under display cameras, wireless charging and eSIM for cellular connection and pressure sensitive touch sensors in the display to replace physical buttons. 

It's unlikely we'll ever see this phone on retail store shelves, but it does show us what's possible with the technology available to manufacturers. Maybe it's pie in the sky, or maybe this is a glimpse at smartphones of the future.